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Published in: BMC Psychiatry 1/2020

Open Access 01-12-2020 | Correspondence

Interpretation of within-group change in randomised trials

Author: Kypros Kypri

Published in: BMC Psychiatry | Issue 1/2020

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Abstract

In medicine, it is common to observe improvement after intervention, at least partly because patients present for care in extremis and would have improved without intervention. Controlling for this counterfactual explanation for improvement is the principle reason to conduct a trial in which patients are randomised to treatment or a control group. Accordingly, it is not reasonable to infer that both interventions are effective when the groups show similar improvements in outcome.
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Metadata
Title
Interpretation of within-group change in randomised trials
Author
Kypros Kypri
Publication date
01-12-2020
Publisher
BioMed Central
Published in
BMC Psychiatry / Issue 1/2020
Electronic ISSN: 1471-244X
DOI
https://doi.org/10.1186/s12888-020-02641-w

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